Granuheap Angle of Repose Instrument (Granutools)

Motivation

Measuring the angle of repose is an essential test in the pharmaceutical field. However, the method for measuring the angle of repose has not evolved for years, and pharmaceutical companies have expressed the need for a more accurate and reproducible measurement method. The GranuHeap instrument meets this need through reproducible, fast, and user-independent measurement.

This measurement can be correlated with the tablet compression process and with many other pharmaceutical processes. GranuHeap measurement provides very high precision, allowing you to accurately compare your powders.

Principle

The GranuHeap instrument is an automated method for measuring heap shape based on image processing and analysis. The GranuHeap principle consists of creating a powder heap on a cylindrical support following a strict initialization protocol.

The user manually fills the tube, which then moves upward at a constant speed. The powder then flows out of the tube to form a heap on the cylindrical support. This support rotates at a controlled speed and a camera takes pictures from different angles.

Granutools' custom heap recognition algorithm determines the position of the powder/air interface. The angle of repose refers to the angle of the isosceles triangle having the same surface area as the projected image of the powder heap. This isosceles triangle corresponds to the ideal shape of a cohesive heap.